A man in Wyoming has been infected with a rare disease transmitted through dog urine, prompting a CDC investigation.
The unnamed man sought medical help after fainting and spending several days with unexplained fever, nausea, sweating and body aches.
Days later, the patient returned to the hospital and tests revealed he had fluid around his lungs and kidney damage.
After a series of tests and learnings working closely with animals, he was diagnosed with leptospirosis, which kills up to one in six patients.
Leptospirosis is transmitted to humans through contact with contaminated urine from animals such as dogs, rats and cattle.
The CDC and the Wyoming Department of Health believe the man became infected through his job, including exposure to three dogs that mysteriously died.
Their investigation also found that Wyoming suffered an outbreak among dogs at the time, with 13 canines testing positive for the disease and four dying due to severe illness.
This is believed to be the first human case of leptospirosis in Wyoming in 30 years.
Doctors had difficulty finding a diagnosis for the patient because leptospirosis typically spreads in areas with high rainfall and waterlogged soil, making it most common in Appalachian states, the Upper Midwest and parts of Texas.
The Wyoming man was treated with antibiotics and sent home from the hospital days later.
Experts warn that dogs should be vaccinated against leptospirosis. Laboratory tests can determine if dogs have antibodies against the disease, indicating that they have been vaccinated.
‘Lifestyle factors thought to increase dogs’ risk of exposure include contact with livestock or wildlife, time spent in kennel environments, and participation in activities that expose them to standing water or mud, such as wandering on croplands, hunting, hiking, or swimming,’ they wrote.
Additionally, all veterinarians and boarding facilities must properly clean up waste to eliminate the spread of infections.
Leptospirosis is caused by the bacterium Leptospira, which is found in soil and water around the world but is most common in subtropical areas with high rainfall, such as Australia, Africa, Southeast Asia, and Central and South America.
When animals such as rats, dogs or cattle are infected with leptospirosis, they may not show symptoms of the disease.
But they may continue to excrete bacteria into the environment continuously or occasionally for several months or even several years.
Humans can become infected through contact with the urine of infected animals.
The Wyoming patient said he had “occupational exposure to dogs,” though it’s unclear what his job was.
“The patient had no known connection to a canine case but was occupationally exposed to body fluids from multiple dogs, including three that died of unknown causes,” the CDC experts wrote in a report.
On the same day the man began experiencing symptoms, three dogs at a local veterinary clinic were diagnosed with leptospirosis. A state analysis revealed that 13 cases had been reported between August and October 2023.
Veterinary records and interviews with staff members showed that sick dogs experienced vomiting, lethargy and decreased appetite.
They also had low levels of blood urea nitrogen and serum creatinine, indicating kidney damage.
Four of the dogs were euthanized or died due to serious illness. Five were held at the same shelter between August and September, but officials did not name the operation.
Leptospirosis infections are not common in the U.S.: Only 100 to 150 are diagnosed each year, of which about 15 percent, or one in six, are fatal.
If left untreated, leptospirosis can lead to kidney failure, meningitis, liver damage, and breathing difficulties.
There are no vaccines available for humans, although a two-dose vaccine is available for dogs. CDC experts said the vaccine is generally only recommended for dogs living in high-risk areas, such as the Appalachian states, the northern Midwest and central Texas.
However, the team said veterinarians are now switching to vaccinating all dogs.
The Wyoming patient was treated with oral antibiotics and discharged from the hospital.